Array substrate and display device having the same

ABSTRACT

The present invention discloses an array substrate and a display device including the same, the array substrate including a display area and a non-display area, wherein the non-display area has a bending region connected to the display area; a first base layer extends from the display area to the bending region; a water-oxygen barrier layer is disposed on the first base layer of the display area; a second base layer is disposed on the water-oxygen barrier layer of the display area and the first base layer of the bending region; a metal trace disposed over the second base layer and extending from the display area to the bending region. In the present invention, a water-oxygen barrier layer only in the display region is provided, and a more reasonable functional layer is designed, which effectively improve stress distribution in the bending region during bending to prevent the metal trace from breakage.

BACKGROUND OF INVENTION Field of Invention

The present invention relates to a field of displays and the like, andparticularly to an array substrate and a display device including thearray substrate.

Description of Prior Art

With the development of active matrix organic light emitting diode(AMOLED) display technology, people's demands on display panels areincreasing, especially on designs of display panel bezels, such asdesigns of narrow bezels, especially designs of ultra-narrow lowerbezels.

In theory, the AMOLED adopts a flexible substrate to realize a structuredesign of the ultra-narrow lower bezel, but the lower bezel of thedisplay panel needs to be bent so that the display area of the displaypanel is unchanged, while the non-display area is folded to a back sideof the display panel. In the actual manufacture process, there are manydifficulties, especially in a bending process, a metal trace in thebending region is stressed and deformed due to bending, which easilyleads to metal trace breakage. Therefore, how to ensure the reliabilityof the metal trace in the bending region, that is, the metal trace isnot damaged due to the bending, is an urgent problem to be solved.

SUMMARY OF INVENTION

In order to solve the above technical problem, the present inventionprovides an array substrate and a display device including the arraysubstrate. By providing a water-oxygen barrier layer only in the displayregion, stress distribution in the bending region during bending can beimproved to prevent the metal trace from breakage when it is bent.

A technical solution to solve the above problem is: the presentinvention provides a display area and a non-display area, thenon-display area having a bending region connected to the display area;a first base layer extending from the display area to the bendingregion; a water-oxygen barrier layer disposed on the first base layer ofthe display area; a second base layer disposed on the water-oxygenbarrier layer of the display area and on the first base layer of thebending region; and a metal trace disposed over the second base layerand extending from the display area to the bending region.

In an embodiment of the present invention, in the display area and thebending region, the array substrate further includes: a buffer structurelayer disposed on the second base layer; a first gate insulating layerdisposed on the buffer structure layer; a second gate insulating layerdisposed on the first gate insulating layer; a dielectric layer disposedon the second gate insulating layer, wherein the metal trace is disposedon the dielectric layer; and a planarization structure layer disposed onthe dielectric layer and the metal trace.

In an embodiment of the present invention, the buffer structure layerincludes a first buffer layer disposed on the second base layer; asecond buffer layer disposed on the first buffer layer; and a thirdbuffer layer disposed on the second buffer layer; wherein the firstbuffer layer is made of silicon dioxide, the second buffer layer is madeof silicon oxynitride, and the third buffer layer is made of silicondioxide.

In an embodiment of the present invention, the first buffer layer has athickness of 450 nm to 550 nm; the second buffer layer has a thicknessof 35 nm to 45 nm; and the third buffer layer has a thickness of 180 nmto 220 nm.

In an embodiment of the present invention, the planarization structurelayer includes a first planarization layer disposed on the dielectriclayer and the metal trace; and a second planarization layer disposed onthe first planarization layer; wherein the first planarization layer andthe second planarization layer are both made of polyimide, and whereinthe first planarization layer has a thickness of 1 μm to 2 μm, and thesecond planarization layer has a thickness of 2 μm to 4 μm.

In an embodiment of the present invention, in the display area, thearray substrate further includes: an active layer disposed on the bufferstructure layer, the active layer having a source region and a drainregion; a first gate layer disposed on the first gate insulating layer;a second gate layer disposed on the second gate layer; a source and adrain, the source extending from the metal trace to the source region ofthe active layer, the drain extending from the metal trace to the drainregion of the active layer; and an anode trace disposed on theplanarization structure layer and connected to the drain.

In an embodiment of the present invention, the anode trace includes afirst protective layer; a first metal layer disposed on the firstprotective layer; and a second protective layer disposed on the firstmetal layer; wherein the first protective layer has a thickness of 10 nmto 20 nm, and the first metal layer has a thickness of 90 nm to 110 nm;and wherein the second protective layer has a thickness of 10 nm to 20nm.

In an embodiment of the present invention, the first base layer and thesecond base layer are both made of polyimide, and the first base layerhas a thickness of 5-15 um, and the second base layer has a thickness of5-15 um.

In an embodiment of the present invention, the metal trace includes asecond metal layer; a third metal layer disposed on the second metallayer; and a fourth metal layer disposed on the third metal layer;wherein the second metal layer has a thickness of 70 nm to 90 nm, thethird metal layer has a thickness of 550 nm to 650 nm, and the fourthmetal layer has a thickness of 70 nm to 90 nm.

In an embodiment of the present invention, the water-oxygen barrierlayer is made of a material including at least one of silicon oxide,silicon nitride, and amorphous silicon.

The present invention also provides a display device including the arraysubstrate.

An advantage of the present invention is that in the array substrate andthe display device including the array substrate of the invention,stress distribution in the bending region during bending can be improvedto prevent the metal trace from breakage when it is bent, which isachieved by providing a water-oxygen barrier layer only in the displayregion and designing a more reasonable functional layer. In addition,the metal trace adopts a multilayered structure oftitanium-aluminum-titanium, which can further enhance the strength ofthe metal trace to mitigate the deformation of the metal trace when itis bent.

BRIEF DESCRIPTION OF DRAWINGS

In order to more clearly illustrate the embodiments or the technicalsolutions of the existing art, the drawings illustrating the embodimentsor the existing art will be briefly described below. Obviously, thedrawings in the following description merely illustrate some embodimentsof the present invention. Other drawings may also be obtained by thoseskilled in the art according to these figures without paying creativework.

FIG. 1 is a schematic structural view of an array substrate according toan embodiment of the present invention.

FIG. 2 is a schematic structural view of a metal trace according to anembodiment of the present invention.

FIG. 3 is a schematic structural view of an anode trace according to anembodiment of the present invention.

Elements in the drawings are designated by reference numerals listedbelow.

1 display device; 10 array substrate; 101 display area; 102 non-displayarea; 1021 bending region; 11 first base layer; 12 water-oxygen barrierlayer; 13 second base layer; 14 buffer structure layer; 15 first gateinsulating layer; 16 second gate insulating layer; 17 dielectric layer;18 metal trace; 19 planarization structure layer; 101 active layer; 102first gate layer; 103 second gate layer; 104 source; 105 drain; 106anode trace; 141 first buffer layer; 142 second buffer layer; 143 thirdbuffer layer; 181 second metal layer; 182 third metal layer; 183 fourthmetal layer; 191 first planarization layer; 192 second planarizationlayer; 1061 first protective layer; 1062 first metal layer; 1063 secondprotective layer; 1011 source region; 1012 drain region.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

With reference to the appended drawings, exemplary embodiments of thepresent invention will be described in detail below. To aid inunderstanding the present invention, like numbers refer to like elementsthroughout the description of the figures, and the description of thesame elements will be not reiterated. For illustration clarity, manydetails of practice are explained in the following descriptions.However, it should be understood that these details of practice do notintend to limit the present disclosure.

The following description of the various embodiments is provided toillustrate the specific embodiments of the invention. The spatiallyrelative directional terms mentioned in the present invention, such as“upper”, “lower”, “before”, “after”, “left”, “right”, “inside”,“outside”, “side”, etc. and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures which are merelyreferences. The spatially relative terms are intended to encompassdifferent orientations in addition to the orientation as depicted in thefigures.

As shown in FIG. 1, in an embodiment, the array substrate 10 of thepresent invention includes a display area 101 and a non-display area102, and the non-display area 102 has a bending region 1021 connected tothe display area 101.

A structure of the array substrate 10 includes a first base layer 11, awater-oxygen barrier layer 12, a second base layer 13, and metal trace18. The first base layer 11 extends from the display area 101 to thebending region 1021; the water-oxygen barrier layer 12 is disposed onthe first base layer 11 of the display area 101, but does not extend toand on the first base layer 11 of the bending region 1021; the secondbase layer 13 is disposed on the water-oxygen barrier layer 12 of thedisplay area 101 and extends to and on the first base layer 11 of thebending region 1021. The metal trace 18 is disposed above the secondbase layer 13 and extends from the display area 101 to the bendingregion 1021.

In the specific manufacture, polyimide is employed to form the firstbase layer 11 having a thickness of 5-15 um, preferably 10 um. Then, atleast one of silicon oxide, silicon nitride, and amorphous silicon isdeposited on the first base layer 11 of the display region 101 to formthe water-oxygen barrier layer 12 having a thickness of 500 nm.Thereafter, the second base layer 13 is formed on the water-oxygenbarrier layer 12 of the display area 101 and the first base layer 11 ofthe bending region 1021. The second base layer 13 and the first baselayer 11 are made of the same material, which is also polyimide. Thesecond base layer 13 has a thickness of 5-15 um. In the display area101, the thickness of the second base layer 13 is preferably 10 um. Inthis embodiment, at least one of silicon oxide, silicon nitride, andamorphous silicon is deposited only on the first base layer 11 of thedisplay region 101. Therefore, in the bending region 1021, there is nowater-oxygen barrier layer 12 corresponding to the metal trace 18, sothat when the bending region 1021 is bent, a neutral surface can be asclose as possible to the metal trace 18, or the neutral surface fallswithin a level where the metal trace 18 is located, to improve thestress generated when the metal trace 18 is bent, preventing the metaltrace 18 from breakage.

In the display area 101 and the bending region 1021, the structure ofthe array substrate 10 further includes a buffer structure layer 14, afirst gate insulating layer 15, a second gate insulating layer 16, adielectric layer 17, and a planarization structure layer 19. In thedisplay region 101, the structure of the array substrate 10 furtherincludes an active layer 101, a first gate layer 102, a second gatelayer 103, a source 104 and a drain 105, and an anode trace 106.

The structure of the array substrate 10 will be described in detailbelow with reference to FIG. 1.

A buffer structure layer 14 is disposed on the second base layer 13. Thebuffer structure layer 14 is provided with a first buffer layer 141, asecond buffer layer 142, and a third buffer layer 143. In a specificmanufacture, a material of silicon oxide is deposited on the second baselayer 13 to form the first buffer layer 141 having a thickness of 450 nmto 550 nm, preferably 500 nm. Thereafter, a material of silicon nitrideis deposited on the first buffer layer 141 to form a second buffer layer142 having a thickness of 35 nm to 45 nm, preferably 40 nm. Thereafter,a material of silicon oxide is deposited on the second buffer layer 142to form a third buffer layer 143 having a thickness of 180 nm to 220 nm,preferably 200 nm.

An active layer 101 is disposed on the buffer structure layer 14 of thedisplay region 101. The active layer 101 is doped with P+ ions, and theactive layer 101 has a source region 1011 and a drain region 1012 andhas a thickness ranging from 45 nm to 55 nm, preferably 50 nm.

A first gate insulating layer 15 is formed on the active layer 101 andthe third buffer layer 143. In a specific manufacture, a material ofsilicon oxide is deposited on the active layer 101 and the third bufferlayer 143 to form the first gate insulating layer 15 having a thicknessranging from 135 nm to 145 nm, preferably 140 nm.

The first gate layer 102 is disposed on the first gate insulating layer15 of the display region 101. In a specific in, molybdenum is depositedto form the first gate layer 102 on the first gate insulating layer 15.The first gate layer 102 has a thickness ranging from 240 nm to 260 nm,preferably 250 nm.

The second gate insulating layer 16 is disposed on the first gateinsulating layer 15 and covers the first gate layer 102 of the displayregion 101. In a specific manufacture, a material of silicon nitride isdeposited on the first gate layer 102 and the first gate insulatinglayer 15 to form the second gate insulating layer 16 having a thicknessranging from 135 nm to 145 nm, preferably 140 nm.

The second gate layer 103 is disposed on the second gate insulatinglayer 16 of the display region 101. In a specific manufacture,molybdenum is deposited on the second gate insulating layer 16 to formthe second gate layer 103 having a thickness of 240 nm to 260 nm,preferably 250 nm.

A dielectric layer 17 is disposed on the second gate insulating layer 16and covers the second gate layer 103 of the display region 101. In aspecific manufacture, a material of silicon oxide is deposited on thesecond gate insulating layer 16 and the second gate layer 103 to formthe dielectric layer 17 having a thickness of 450 nm to 550 nm,preferably 500 nm. Then, via holes are formed in the display region 101,and the via holes penetrate the dielectric layer 17 to the active layer101, wherein one of the via holes corresponds to the source region 1011,and another one of the via holes corresponds to the drain region 1012.

A metal trace 18 is disposed on the dielectric layer 17. As shown inFIG. 2, the metal trace 18 sequentially includes a second metal layer181, a third metal layer 182, and a fourth metal layer 183. In aspecific manufacture, titanium is deposited in the via hole and on thedielectric layer 17 to form a second metal layer 181 having a thicknessof 70 um to 90 nm, preferably 80 nm; then aluminum is deposited to forma third metal layer 182 having a thickness ranging from 550 nm to 650nm, preferably 600 nm; and then titanium is deposited to form a fourthmetal layer 183 having a thickness of 40 nm to 60 nm, preferably 50 nm,thus forming the metal trace 18 having a multi-layer structure oftitanium-aluminum-titanium. The metal trace 18 in the via holecorresponding to the source region 1011 is served as the source 104, andthe metal trace 18 in the via hole corresponding to the drain region1012 is served as the drain 105. The multi-layered structure oftitanium-aluminum-titanium can further enhance strength of the metaltrace 18 to mitigate the stress generated when the metal trace 18 isbent, and to avoid the breakage phenomenon of the metal trace 18.

The planarization structure layer 19 is disposed on the dielectric layer17 and the metal trace 18. The planarization structure layer 19 includesa first planarization layer 191 and a second planarization layer 192.The first planarization layer 191 is disposed on the dielectric layer 17and the metal trace 18, and the second planarization layer 192 isdisposed on the first planarization layer 191. The first planarizationlayer 191 and the second planarization layer 192 are both made ofpolyimide. Specifically, after the metal trace 18 is prepared, amaterial of polyimide is deposited on the dielectric layer 17 and themetal trace 18 to form a first planarization layer 191 having athickness of 1 μm to 2 μm, preferably 1.5 μm. The material of polyimideis then deposited again to form a second planarization layer 192 havinga thickness of from 2 μm to 4 μm, preferably 3 μm. The two planarizationlayers are formed by the two times of deposition, which further improvethe flatness of the planarization structure layer 19. Then, a connectionhole is formed in the planarization structure layer 19, and theconnection hole penetrates from the planarization structure layer 19 toa surface of the drain electrode 105, so that the drain 105 is exposedin the connection hole.

The anode trace 106 is disposed on the planarization structure layer 19and connected to the drain 105. As shown in FIG. 3, the anode trace 106includes a first protective layer 1061, a first metal layer 1062, and asecond protective layer 1063. In a manufacture process, a material ofindium tin oxide is deposited on the second planarization layer 192 andin the connection hole to form the first protective layer 1061 having athickness of 10 nm to 20 nm, preferably 15 nm; silver is deposited toformed a first metal layer 1062 having a thickness of 90 nm to 110 nm,preferably 100 nm; then a material of indium tin oxide is deposited toform a second protective layer 1063 having a thickness of 10 nm to 20nm, preferably 15 nm, thus forming the anode trace 106 having amulti-layered structure of indium tin oxide-silver-indium tin oxide.

The present invention also provides a display device 1 including thearray substrate 10 described in this embodiment. Of course, one of maindesign points of the present invention lies in the array substrate 10.As for the other structures or devices of the display device 1, such asa color filter substrate and a thin film encapsulation layer, thedetails are not described herein for brevity.

While the invention has been described by way of example and in terms ofthe preferred embodiments, it is to be understood that the invention isnot limited to the disclosed embodiments. To the contrary, it isintended to cover various modifications and similar arrangements.Therefore, the scope of the appended claims should be accorded thebroadest interpretation so as to encompass all such modifications andsimilar arrangements.

What is claimed is:
 1. An array substrate, comprising: a display area and a non-display area, the non-display area having a bending region connected to the display area; a first base layer extending from the display area to the bending region; a water-oxygen barrier layer disposed on the first base layer of the display area; a second base layer disposed on the water-oxygen barrier layer of the display area and on the first base layer of the bending region; and a metal trace disposed over the second base layer and extending from the display area to the bend region, wherein the metal trace has a multi-layer structure of titanium-aluminum-titanium.
 2. The array substrate according to claim 1, wherein in the display area and the bending region, the array substrate further comprises: a buffer structure layer disposed on the second base layer; a first gate insulating layer disposed on the buffer structure layer; a second gate insulating layer disposed on the first gate insulating layer; a dielectric layer disposed on the second gate insulating layer, wherein the metal trace is disposed on the dielectric layer; and a planarization structure layer disposed on the dielectric layer and the metal trace.
 3. The array substrate according to claim 2, wherein the buffer structure layer comprises: a first buffer layer disposed on the second base layer; a second buffer layer disposed on the first buffer layer; and a third buffer layer disposed on the second buffer layer; wherein the first buffer layer is made of silicon dioxide, the second buffer layer is made of silicon oxynitride, and the third buffer layer is made of silicon dioxide; and wherein the first buffer layer has a thickness of 450 nm to 550 nm, the second buffer layer has a thickness of 35 nm to 45 nm, and the third buffer layer has a thickness of 180 nm to 220 nm.
 4. The array substrate according to claim 2, wherein the planarization structure layer comprises: a first planarization layer disposed on the dielectric layer and the metal trace; and a second planarization layer disposed on the first planarization layer; wherein the first planarization layer and the second planarization layer are both made of polyimide, and wherein the first planarization layer has a thickness of 1 μm to 2 μm, and the second planarization layer has a thickness of 2 μm to 4 μm.
 5. The array substrate according to claim 2, wherein in the display area, the array substrate further comprises: an active layer disposed on the buffer structure layer, the active layer having a source region and a drain region; a first gate layer disposed on the first gate insulating layer; a second gate layer disposed on the second gate layer; a source and a drain, the source extending from the metal trace to the source region of the active layer, the drain extending from the metal trace to the drain region of the active layer; and an anode trace disposed on the planarization structure layer and connected to the drain.
 6. The array substrate according to claim 1, wherein the anode trace comprises: a first protective layer; a first metal layer disposed on the first protective layer; and a second protective layer disposed on the first metal layer; wherein the first protective layer has a thickness of 10 nm to 20 nm, and the first metal layer has a thickness of 90 nm to 110 nm; and wherein the second protective layer has a thickness of 10 nm to 20 nm.
 7. The array substrate according to claim 1, wherein the first base layer and the second base layer are both made of polyimide, and the first base layer has a thickness of 5-15 um, and the second base layer has a thickness of 5-15 um.
 8. The array substrate according to claim 1, wherein the metal layer comprises: a second metal layer; a third metal layer disposed on the second metal layer; and a fourth metal layer disposed on the third metal layer; wherein the second metal layer has a thickness of 70 nm to 90 nm, the third metal layer has a thickness of 550 nm to 650 nm, and the fourth metal layer has a thickness of 40 nm to 60 nm.
 9. The array substrate according to claim 1, wherein the water-oxygen barrier layer is made of a material comprising at least one of silicon oxide, silicon nitride, and amorphous silicon.
 10. A display device, comprising the array substrate according to claim
 1. 